• Journal of Ship and Ocean Technology
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• v.9 no.4
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• pp.1-10
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• 2005

The effect of buoyancy orientation on turbulent channel flow has been investigated using DNS (direct numerical simulation). Grashof number is kept at 9.6 $\times 10^{5}$ while changing the orientation of the buoyancy vector to be parallel or perpendicular to the channel walls. Four study cases can be distinguished during this research namely; streamwise, wall-normal unstable stratification, wall-normal stable stratification and spanwise oriented buoyancy. The driving mean pressure gradient used in all cases is adjusted to keep mass flow rate constant while friction Reynolds number is around 150. At this Grashof number, the skin friction shows decrement in the unstable and stable stratification and increment in the other two cases. Analyses of the changes of flow structure for the four cases are presented highlighting on the mean quantities and second order statistics.

• Journal of the Korea Society of Computer and Information
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• v.7 no.1
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• pp.27-32
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• 2002

Software reuse was focused for the way of improving programmer productivity from the crisis of software. Object oriented technology impact on overall area of software engineering, such as software analysis , Programming language. testing and maintenance. The new concepts, Class, Inheritance and encapsulation, not only introduce new testing problems and they raise a new challenging question of how to conduct regression testing for 0-0 programs the first problem of regression testing is how to identify the affected components due to the changes of some components. We propose a method firewall to enclose all classes and methods affected by the changes to one or more methods in Inheritance relation

• Journal of the Korean Magnetics Society
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• v.5 no.5
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• pp.690-694
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• 1995

Reducing media noise is a key to realizing high areal recording density. However, perpendicularly oriented Co-Cr films, stong candidates for high density recording media, have received little attention in terms of recording noise. We studied the noise characteristics of Co-Cr based alloy films by varying the compositionally separated structure. Co-Cr films with fine compositionally separated microstructure were observed to have low noise, which recording density dependence were negative or week. Studies on control of the microstructure and magnetic properties in combination with noise analysis are important to realize high density recording media.

• Journal of the Korea Society of Computer and Information
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• v.23 no.1
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• pp.139-145
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• 2018

This paper recommends flipped learning as a method to improve the learning abilities and the level of software utilization when it comes to using computers in children education institutes. Flipped learning enables a class fully making use of the up-to-date multimedia-related technology. Especially, flipped learning leads a participation-oriented class rather than lecture-based ones. Young child's teachers can, not only improve their capabilities to utilize multimedia, but also manage classes that follow the trend of the fourth industrial revolution. Therefore, this paper introduces the importance of media education when it comes to training preliminary teachers and suggests a flipped learning curriculum. This paper finds significance in future efficient education for raising creative and integrated thinking children.

• Annual Conference of KIPS
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• 2012.11a
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• pp.1497-1499
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• 2012

전통적인 소프트웨어 개발에서는 초기 요구사항을 정확히 판단하고 분석하는 것이 중요하다. 이를 위해 B.Boehm은 가치혁신 요구공학을 제안하지만, 이는 기존의 개발 방법 기반이다. 본 논문에서는 가치 혁신 요구공학 개선을 위해, 유스케이스 기반의 요구공학 방법을 제시와, 요구사항과 유스케이스의 우선순위 도출 방법을 제안한다. 이를 위해 어려운 시스템 요소(하드웨어와 소프트웨어)를 기본 단위인 유스케이스 요소와, 유스케이스 점수(Use Case Point) 개념을 적용하여 유스케이스 중요도를 도출한다. 그 기본 단위 내의 분석을 통해 쉽게 요구사항 추출 및 우선순위화를 한다. 이는 테스트 단계에서 우선순위화된 테스트 케이스를 적용이 가능한다고 본다.

• Journal of Aerospace System Engineering
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• v.15 no.6
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• pp.1-9
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• 2021

In this study, a new design of an extension-type actuator (ExACT) is proposed based on a chevron structure with displacement amplification mechanisms by local heating. ExACT comprises diamond-shaped displacement amplification structures (DASs) containing axially oriented V-shaped chevron beams, a support bar that restricts lateral heat deformation, and a loading slot for thin-film heaters. On heating the thin film heater, the diamond-shaped DASs undergo thermal expansion. However, lateral expansion is restricted by the support bar, leading to displacement amplification in the axial direction. The performance parameters of ExACT such as temperature distribution and extended displacement is calculated using thermo-mechanical analysis methods with the finite element method (FEM) tool. Subsequently, the ExACTs are fabricated using a polymer-based 3D printer capable of reproducing complex structures, and the performance of ExACTs is evaluated under various temperature conditions. Finally, the performance evaluation results were compared with those of the FEM analysis.

• International Journal of Computer Science & Network Security
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• v.21 no.12
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• pp.223-227
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• 2021

A treatment based on the algebraic operations on fuzzy numbers is used to replace the fuzzy problem into an equivalent crisp one. The finite difference technique is used to replace the continuous boundary value problem (BVP) of arbitrary order 1<α≤2, with fuzzy boundary parameters into an equivalent crisp (algebraic or differential) system. Three numerical examples with different behaviors are considered to illustrate the treatment of the singular perturbed case with different fractional orders of the BVP (α=1.8, α=1.9) as well as the classical second order (α=2). The calculated fuzzy solutions are compared with the crisp solutions of the singular perturbed BVP using triangular membership function (r-cut representation in parametric form) for different values of the singular perturbed parameter (ε=0.8, ε=0.9, ε=1.0). Results are illustrated graphically for the different values of the included parameters.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.24 no.2
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• pp.333-336
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• 2020

AI-powered robot news is drawing attention as artificial intelligence technology is fully spread in the news distribution field. Robot news still has many technical and ethical problems, but academic research on this is insufficient. This study analyzes the issue of robot writing in artificial intelligent based robot journalism industry using SWOT analysis. As a result, the advantages of big data processes, accurate information gathering, high efficiency and disadvantages such as lack of independent arguments and lack of evidence and opportunities for technical development, government support, academic development, and industrial applications, and threats such as uncritical acceptance and lack of talent have been found. This study suggests three future-oriented directions, such as human-machine collaboration, intelligent news, and chat-bot, through previous studies on the development direction of robot journalism-based article writing.

• Food Science and Industry
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• v.53 no.1
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• pp.92-100
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• 2020

Recently, a lot of consumers in the United States are trying to find out the diverse Asian foods due to the raw material used,sauce,flavor,taste, and cooking philosophy. Asian fare has boomed up in the past decades at restaurants and retail food markets. These phenomena are considered to continue since many Americans become more cautious for health since they believe the traditional Asian foods are better for health than European, Latin, and traditional American diets. The increase of Asian population in America also induce the increased consumption of Asian foods, and those who traveled and tasted Asian foods during their journey want to take Asian foods after back home. Several sauces including gochujang, ramen, and seaweed snack are examples of Asian foods consumed in a large quantity. Many Asian food and material suppliers are trying to pioneer and penetrate American food market with exotic multifaceted Asian cuisine.

• Korean Journal of Metals and Materials
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• v.50 no.12
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• pp.867-871
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• 2012

The microstructure and texture of TiN coatings on a Ni-based super-alloy were characterized by the automated version of electron backscatter diffraction (EBSD), EBSD techniques were used to investigate the very fine TiN grain shape and crystal orientation. This study confirmed that EBSD techniques provide a very useful tool for characterization of coating materials. The TiN grains had a special texture, a {001}-fiber texture in the coating layer. It was also found that, in severe environments, the coating performance of equiaxial and randomly oriented TiN is superior to that with columnar structures.